Oscillating magneto



F. W. ANDREW.

OSCILLATING MAGNETO. APPLICATION men SEPT. 18. 1919. RENEWED APR-30.1920.

1,416,670. atent d May23',1922.

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F. W. ANDREW.

OSCILLATING MAGNETO. APPLICATION FILED SEPT-18.1919. RENEWED APR. 30.1920.

1,416,670. Patented May 23, 1922.

3 SHEETS-SHEET 2.

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F. W. ANDREW.

OSGiLLATING MAGNETO.

APPLICATION FILED SEPT- I8. 1919. RENEWED APR.30,192 O.-

1,416,670. a Patented May 23,1922.

3 SHEETS-SHEET 3.

Frederic/t l l/ awe/W600 UNITED STATES PATENT OFFICE.

rnnnnmox w. ANDREW, or BROOKLYN, new YORK, ssrenoa TO EisEMANN MAGNETOconrona'rron, on BROOKLYN, NEW YORK, A oonronarron OFNEW YORK.

Specification of Letters Patent. Patented May 23, 19.22.

Application filed September 18, 1919, Serial No. 324,543; Renewed April30, 1920. Serial No. 377,970.

To aZZ whom it may concern.

Be it known that I, F nnonnron WILLIAM ANDREW, a citizen of the UnitedStates, and a resident of the city of New York, borough of Brooklyn,county of Kings, and State of New York, have invented certain new anduseful Improvements in Oscillating Magnetos, of which the following isafull, clear, and exact specification.

My invention relates to electric current generators, more particularlyto those used in electric ignition systems employed in connection withinternal combustion engines, and consists in devising a novel mechanismfor oscillating the movable part of a genorator, an example whereof isherein described with reference to the accompanying drawings, whereinFig. 1 is a front elevation of a magneto, provided with the mechanismfor oscillating its shaft, constructed according tomy invention;

Fig. 2 is a similar View with the oscillator arm, and the nut-cap,removed;

Fig. 3 is a longitudinal sectional view on line 3-3, indicated in Fig.1, looking in the direction indicated by the arrow pointing to thesection line; i

Fig. i is a cross-sectional view on line it-"ti, indicated in Fig. 3,looking in the direction indicated by the arrow pointing to the sectionline;

Figs. 5 to 9, illustrate details of construction, Fig. 5 being a sideelevation, partly sectional view of one of the spring arms; Fig. (3 arear elevation of the other spring arm; Fig. 7 a sectional view thereofon line 7-7, indicated in Fig. 6; Fig. 8 a front view, and Fig. 9 a sideview of the osciilator arm.

The oscillator mechanism is constructed as follows:

The flanged bushing 11 is keyedor otherwise secured to the magneto shaft12, the end whereof is screw-threaded correspondingly to the interiorscrew-thread of the flanged capnut 13. The. body or'the nut 13 is tittedinto the bushing 11. which is recessed as shown at 11 in Fig. 2, and theoscillator arm 1% (see Figs. 8 and 9) is litted thereon; the centralpart of the slot 15 being widened i'forrespondingly to the interiorannular recess 16 of the bushing 11 to permit passing therethrough ofthe body of "the sleeve 18, into which the inner end of the'spring 21 isinserted. At the end of the arm 17 the flange 2G is formed, which thoughhelpful in the operation of the device, i not essential. When the arm 17is mounted on the bushing 11, the end of the sleevelS abuts against theflange 23 of the said bushing, andthe said arm is thus rotatable, butnot longitudinally movable thereon. The spring 21 is what is technicallytermed a helical spring, or more commonly called a spring of theclock-spring type.

More broadly speaking, I may refer to the spring 21' as one in which thearms of the coils is substantially coincident with the magneto shaft 12on which the spring is mounted. A spring of thistype does not requireany housing and is practically free from friction during the operationoi. the oscillator.

The shape of the other spring-arm 24:, is hown in Figs. 2 and 6. Theperforation 25 in this arm is also snugly fitted upon the bushing 11',and a stud 26 is set in its end for connecting thereto the other outerend of the spring 21. The flange 27 on theend of this arm 24 extends inopposite direction to the flange 20 on the end of the arm 17, wherebyboth flanges are brought in alignment.

A plate 29 is secured by the nuts 32 to the posts 28, set in the casing30 of the magneto. On this plate 29 a tongue 31 is formed, extendinginto the path of the spring arms 17 and 24!. and forming a stoparresting the movement of each of the arms when actuated by reaction ofthe spring 21, as explained further on in the description of theoperation of this device.

The oscillator arm 141 is fitted upon the recessed forward end of thebushing 11, (see Fig. 2) and is secured thereon, and to the magnetoshaft 12, by the flanged capnut The oscillator arm 14- is thus rigidlyconnected with the shaft 1.2 of the magneto like a crank, so that byswinging it the magneto shaft, and the rotor mounted thereon, arecorrespondingly actuated. Thereby also, as shown in Fig. 3, thespring-arms l7 and 24:, which are rotatably mounted on the bushing 11,are held in their position. The stud 33 is set in the oscillator arm inposition to enter into the space between the spring-arms l7 and 24 (seeFig. 2) held open by the stop 31 separating them. This stud 33 is thusin position to engage either one oi? the arms 17 and 2%, according to inwhich direction the oscillator arm is swung. Each one oi? the twospring-arms 17 and 2% being connected to one end of the spring 21., andeach being prevented by the stop 31 from moving when the other is swungaway from the stop, the spring 21. is tensioned by moving the oscillatorarm 14- in either direction, and reacts when the force, moving theoscillator arm,

ceases to act. By the reaction oi the spring, the springarm, which wasthus swung away from the sto 11, acting upon the stud 33, imparts to thes illator arm 1%, a short but quick impulse in reverse direction. Thespring-arm, thus acting on the oscillator arm is stopped by coming incontact with the fixed stop 31, whereas the stud 33 abuts against theother arm, which then acts as a cushion and stop "for the oscillatorarm. Theoscillator arm let being rigidly connected with the magnetoshaft 1.12, the latter, and the rotor, or other rotatory part of themagneto, are by the reaction oi the spring 21 rapidly swung through anarc, whereby electric current required for the production of theignition spark, generated.

The movement of the oscillator arm lid to elfect the tensioning ot thespring 2] may be, and preferably is, produced by a cam, or a two ortour-pointed star-wheel, mounted on the engine shaft, or upon anintermediate shaft, driven from the engine shaft, in the requiredposition to engage the oscillator arm. The particulars oi? theconstruction of these details are determined by the design of theengine, number of cylinders, etc. and as they form no part of myinvention, they are not shown in the drawings and not described indetail.

My improved oscillating mechanism may be used on magnetos or otherelectric current generators, designed to be driven in either direction,the actuating spring being torn sioned, and reacting equally, whetherthe arm 17, connected to its inner, or the arm 24, connected to itsouter end, is acted upon. Another advantage resulting from my inventionis in that the other spring-arm, the one not acted upon by theoscillator arm l i, acts as a cushion in stopping the swing of theoscillator arm almost instantly and with a minimum of vibration, in theposition, in which it to he engaged by the next point of rotatingstar-wheel. This positively prevents a miss oi? the oscillator arm 1i bythe cam, StzHf-illlGQl, or other device actuating it, so ii'requentlyhappening in ignition apparatus provided with oscillating mechanism ofother coi'istruction, and also the jamming Oil the driving part, cam,star-wheel, etc, with the oscillator arm a"ten occurring when nopositive step is provided, and also avoids jarring oi. the parts againsta noncushioued stop oi the oscillator arm.

in Further ad antagc oi my new oscillator resides in the use oi a springwhich does not require to be coniined in a casing. This not onlysimplifies the construction (and thus reduces the cost oi manufacture),but also materially increases the lite oi? the oscillator. It is awell-known :Et'act that the main trouble with oscillators oi priorconstruction is spring breakage. That is particularly true ofoscillators using a coiled spiral spring, which must be bent intocircular shape and confined in a housing. AS the spring contracts andexpands, the coils rub against the walls oil? the housing and are soonworn to a point oi breakage. in my invention, this serious difficultyand objection are entirely eliminated.

1 claim as my invention:

1. An oscillating mechanism tor a magneto or other electric currentgenerator, the mechanism com n'ising a coiled spring and two armsrotatably mounted on the magi'ieto shaiit, each of said arms beingconnected to one end of said spring, an arm rigidly secured to themagneto shalt, means on said last-mentioned arm for moving either o'l.oi said two arms, and a fixed stop in the path oi said two arms iorlimiting the movement oi each in one direction. 7

An oscillating mechanism for a magneto or other electric currentgencratcn'. the mechanism comprising a sleeve rotatablv mounted on themagneto slurtt, an arm int-egral with said sleeve. a coiled springhaving its inner end connected to said sleeve. a sec: ond arm alsorotatably mounted on the magneto shait and connected to the other end ofsaid spring, a iixed stop for limiting the movement or? each oi said twoarms in one direction, an arm rigidly secured to the magneto shaft, andmeans on said last-mew tioned arm for engaging either of the armsconnected to the ends oi. said spring.

3. An oscillating mechanism 'tor a magneto or other electric currentgenerator, the mechanism comprising a coiled spring, two arms rotatablymounted on the magneto shaft, each of said arms being connected to oneend oi said spring, a fixed stop for lim iting the movement of each armin one direction, an arm rigidly secured to the magneto shaft andadapted to be intermittently actuated, and means on said last-mentionedarm adapted to engage either of the two arms connected to the ends ofsaid spring.

t. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising a pair ofmembers rotatably mounted011 the magneto shaft, spring means connected to said members andadapted normally to urge them toward each other, means for limiting themovement of said members under the action of said spring means, and anintermittently operable arm fixed on the magneto shaft for engagingeither of said members and actuating the same against the tension ofsaid spring means, whereby the actuated member will under the action ofsaid spring means impart an accelerated return movement to said arm.

5. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising a pair of oscillating membersmounted on the magneto shaft, a coiled spring also mounted on themagneto shaft and connected at its ends to said members, said springbeing so constructed and arranged that the axis of the coils issubstantially coincident with the axis of said shaft, an arm operativelyconnected with the magneto shaft and adapted to move either member fromits normal position against the tension of said spring, whereby theactuated member will impart an accelerated return movement to said armunder the action of the tensioned spring, and means for holding eithermember against movement during the operation of the other member.

6. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising an intermittently operable armrigidly secured to the magneto shaft, a pair of rotatable members havinghub portions for mounting said members on the magneto shaft, saidmembers being arranged to engage said arm on opposite si es thereof, ahelical spring for rocking said members independently of each other inopposite directions, whereby the operation of said arm in eitherdirection moves one of said members against the tension of said helicalspring, so that the release of said arm permits the spring-pressedmember to movethe arm quickly back to normal position, and means forholding either member against movement during the operation of the othermember.

7. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanlsm comprisinga helical spring and twoindependently rotatable arms, means on said arms for mounting them onthe magneto shaft, each of said arms being connected to one end of saidspring, means for actuating either arm against the action of saidhelical spring, and means for holding either armagainst movement duringthe operation of the other arm.

8. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising a helical spring and twoindependently rotatable arms mounted on the magneto shaft, each of saidarms being connected to one end of said spring, means for actuatingeither arm against the action of said. helical spring, each of said armsbeing arranged to act as a yieldable stop for said actuating means andthe returning arm, and means for holding either arm against movementduring the operation of the other arm.

9. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising a coiled spring mounted on themagneto shaft, said spring being so constructed and arranged that theaxis of the coils is substantially coincident with the axis of saidshaft, an intermittently operable arm rigidly connected to the magnetoshaft and yieldably held in normal position by said spring, and meanswhereby the actuation of said arm in either direction from normalposition places said spring under tension, so that the release of saidarm causes said spring to return the arm to normal position.

10. An oscillating mechanism for a magneto or other electric currentgenerator, the mechanism comprising a pair of rotatable members havinghub portions for mounting said members on the magneto shaft, a coiledspring also mounted on the magneto shaft, said spring being soconstructed and arranged that the axis of the coils is substantiallycoincident with the axis of said shaft, means on each of said membersfor engaging one end of said spring, an arm for actuatin said members,and stop means for holding either end of said spring stationary duringthe operation of said arm in either direction to place said spring undertension.

FREDERICK W. ANDREWV.

Vitnesses i CHARLES S. SKINNER, LOUISE KELLER.

